Printed Circuit Board (PCB) is a physical support for the electronic products, and is an important component for signal transmission. The signal (especially differential signal) transmission on a printed circuit board requires high impedance continuity of signal lines. On the printed circuit board, signal lines in different layers are connected via connection structures. In a case where there is other conductive layer between layers in which signal lines connected via a connection structure are located, a region of the conductive layer surrounding the connection structure is hollowed out, the hollowed out region is hereafter also referred to as an anti-pad for the connection structure. An impedance of the connection structure is typically much less than that of the signal lines.